/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.hadoop.hive.ql.udf.generic;

import org.apache.commons.lang3.StringUtils;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedExpressions;
import org.apache.hadoop.hive.ql.exec.vector.expressions.StringTrimCol;
import org.apache.hadoop.hive.ql.exec.vector.expressions.StringTrimColScalar;

/**
 * UDFTrim.
 *
 */
@Description(name = "trim",
    value = "_FUNC_([LEADING | TRAILING | BOTH] [chars] FROM str) | _FUNC_(str[, chars]) - " +
            "Removes the leading/trailing or both pad characters from str",
    extended = "Example:\n"
    + "  > SELECT _FUNC_('   facebook  ') FROM src LIMIT 1;\n" + "  'facebook'\n"
    + "  > SELECT _FUNC_(BOTH 'xy' FROM 'xyyxFacebookxy');\n" + "  'Facebook'\n"
    + "  > SELECT _FUNC_(' ' FROM ' Facebook  ');\n" + "  'Facebook'\n"
    + "  > SELECT _FUNC_(LEADING ' ' FROM ' Facebook  ');\n" + "  'Facebook  '\n"
    + "  > SELECT _FUNC_('xyfacebookyyx', 'xy');\n" + "  'facebook'")
@VectorizedExpressions({ StringTrimCol.class, StringTrimColScalar.class})
public class GenericUDFTrim extends GenericUDFBaseTrim {
  public GenericUDFTrim() {
    super("trim");
  }

  @Override
  protected String performOp(String val, String trimChars) {
    return StringUtils.strip(val, trimChars);
  }

}
